不同处理方法同种异体半月板移植修复兔膝关节软骨的远期效果比较

Long-term effects of meniscal allograft transplantation to repair rabbit knee cartilage by different methods

背景:目前尚无理想的材料来替代半月板,半月板移植就成为半月板损伤保留半月板功能较为可行的治疗方法。目前移植半月板的保存方法主要是新鲜半月板、低温保存的半月板和冻干保存的半月板。目的:观察经不同方法处理后的兔半月板移植后的远期效果差异。方法:成年新西兰大白兔70只,其中30只作为供体取出半月板。将原有的半月板切除制成半月板缺失模型。随机将大白兔分为4组,每组10只。①半月板缺失组作为对照。②新鲜半月板组移植新鲜半月板。③低温半月板组移植低温保存的半月板。④冻干半月板组移植冻干保存的半月板。30个供体其中10个行新鲜移植,另20个分别行低温保存、冻干保存1周后移植。术后12个月处死兔取标本,进行动物一般观察。半月板大体观察和组织学观察。结果与结论:移植兔切口均愈合好,无死亡。大体观察:新鲜半月板移植组外形、质地和弹性均接近正常半月板。胫骨平台覆盖好,胫骨平台和股骨髁软骨无额外磨损。低温保存、冻干保存半月板移植组半月板边缘愈合好,但是体积缩小,弹性差。胫骨平台有部分没有半月板覆盖。病理观察:新鲜移植半月板切片显示胶原纤维排列、软骨细胞的形态、数量和分布,均与正常半月板相近,而低温保存、冻干保存半月板移植组的半月板切片显示胶原纤维稀疏,数量较新鲜移植的半月板少。结果表明,同种异体半月板移植能够成活,并且能具有一定的结构和功能,防止膝关节退变。但是以新鲜移植的半月板效果最好。低温保存和冻干保存的半月板术后1年出现不同程度的退变和体积缩小。

BACKGROUND： There are no ideal substitutes for meniscus. Meniscal allograft transplantation has become a feasible method to retain meniscal function following injury. Currently, the meniscus conservancy methods include fresh meniscus, low temperature preserved meniscus; freeze-dried meniscus. OBJECTIVE： To observe the long-term effects of meniscus allograft transplantation by different methods. METHODS： A total of 70 adult New Zealand rabbits were used, and 30 were selected as meniscus donors. The remaining 40 rabbits were divided into 4 groups （n=10）： after meniscectomy, control group was not treated; fresh group underwent fresh meniscus allograft transplantation; low temperature group underwent low temperature preserved meniscus allograft transplantation; freeze-dried group underwent freeze-dried meniscus allograft transplantation. Of 30 donors, 10 received fresh meniscus transplantation, and the other received temperature preserved meniscus and freeze-dried meniscus transplantation 1 week after low temperature and freeze dried preservation. The rabbits were sacrificed 12 months after surgery for gross and histological observation. RESULTS AND CONCLUSION： The meniscus allografts of rabbits healed well, and no rabbits died. Gross observation showed that the appearance and elasticity of fresh meniscus group was similar to normal meniscus; tibial plateau was covered well, with no additional wearing in the cartilage of tibial plateau or condyles of femur. In low temperature and freeze-dried preservation groups, the meniscus grafts healed well, but their volume was small and the elasticity was poor; tibial plateau was only partially covered. Pathological observation suggested that fresh meniscus group had orderly arranged collage fiber and similar chondrocyte appearance, number and distribution to normal meniscus, while sparse collagen fiber and small number of meniscus grafts were observed in the other groups. Results show that meniscal allografting can survive, retain certain function and structure and prevent the degenerative changes of the knee joint. Moreover, fresh meniscal grafts exhibit best effects, as the grafts following low temperature or freeze-dried preservation degenerate and their volume diminish 1 year following meniscectomy.